An evidence-based, peer-reviewed journal for practicing clinicians in the field of dermatology
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15 JCAD JOURNAL OF CLINICAL AND AESTHETIC DERMATOLOGY February 2018 • Volume 11 • Number 2 R E V I E W L Lasers have been used in dermatology for over 50 years. Specific to cutaneous lasers, the technique of selective photothermolysis damages a specific target, such as a blood vessel, while sparing surrounding tissue. Three essential requirements must be met in cases of selective photothermolysis: 1) a wavelength that penetrates deeply enough and is preferentially absorbed by the chromophore or target, 2) an exposure duration (pulse width and pulse duration) less than or equal to the thermal relaxation time (TRT) of the target, and 3) sufficient energy (fluence) to cause irreversible damage to the target. 1 In the treatment of vascular lesions, target vessel damage by heated oxyhemoglobin yields vascular injury, which includes coagulation, perivascular collagen damage, and vessel wall necrosis with minimal damage to surrounding epidermis, capillaries, and dermal tissue. 2 Selective photothermolysis allows clinicians and trained aestheticians to treat pigmented and vascular lesions, perform facial resurfacing, and remove hair in select areas. Although one report was clearly against periocular use of lasers, in practice, laser treatments are frequently performed in the eyelid and periocular regions, especially in laser epilation. 3 The eyes are susceptible to injury due to the thinner eyelid skin. In addition, there are several pigment-rich chromophores, such as retinal pigment epithelium and the iris, that can also absorb laser energy. 4 Previous research shows that melanin in the retinal pigment epithelium absorbs more energy at shorter wavelengths than at longer wavelengths. 5 Due to this anatomical limitation, precautions must be taken when treating periorbital areas to decrease the risk of thermal injury and blindness. Patients who are not given ocular protection devices, such as wavelength-specific goggles or spectacles, are often instructed to close their eyes during laser treatment of periorbital areas. However, the eyelids are too thin to sufficiently protect the eye from injury. 5 In addition, Bell's phenomenon, when the eyes naturally roll upwards upon eyelid closure, can cause the pigmented iris to enter the laser's penetration range and absorb the incident radiation, leading to injury of the iris and posterior structures. 6 Patients with light-colored eyes are especially prone to injury in the posterior eye structures, as the pigmented retinal epithelium, and not the iris, tends to absorb the incident radiation. 6 LASER INJURIES OF THE EYE Mechanisms of injury. Short wavelength lasers, such as potassium titanyl phosphate (KTP) and pulsed dye (PDL) lasers, produce photocoagulation (photothermal) damage, while long wavelength, infrared, and near-infrared lasers (e.g., diode, Nd:YAG lasers) produce either photodisruption (photomechanical) or photocoagulation damage. 7 In photocoagulation, the tissue generates enough heat to denature proteins, and increases in retinal temperature of 40°C to 60°C can be observed. 5 In photodisruption, an explosive acoustic shock is generated that shears, fragments, and perforates tissue. Clinically, the 1064nm Nd:YAG laser, which is implicated in the majority of laser-induced ocular injuries, is capable of causing retinal hemorrhage, vitreous hemorrhage, scarring, preretinal membrane formation, and retinopathy when the radiation is absorbed by the melanin-rich retinal pigment epithelium. 5 The Nd:YAG laser can cause significant injury to the eye and surrounding skin, compared to shorter wavelength lasers, because it can penetrate deeper layers of the skin. Longer wavelength lasers (e.g., 755–795nm alexandrite to 1064nm Nd:YAG lasers) also tend to be weakly A B S T R A C T BACKGROUND: The eye is a vulnerable and commonly injured organ in cosmetic laser procedures of the face. Treatment of the eyelids and periorbital areas increases this risk, especially when ocular protection devices are not used or are removed during the procedure. A study has shown that injury from laser epilation of the periocular areas is one of the most common causes of litigation in cutaneous laser surgery. OBJECTIVE: The goal of this review is to determine the causes of ocular injury in cosmetic laser procedures and derive lessons on critical safety elements to prevent future injury. METHODS: We conducted a review of the current literature through a PubMed search on case reports of ocular injury in cosmetic laser treatments of the face. Twenty-one cases are examined. RESULTS: In more than 62 percent of cases, ocular protection was not used or protection was used but removed during the procedure to treat areas close to the eye. However, despite the proper use of intraocular corneal shields and wavelength- specific goggles, accidents occurred in 33 percent of cases. CONCLUSION: Ocular protection devices are essential to prevent most cases of laser-induced eye injury. Use of high fluence and long wavelength lasers increases the risk of ocular injury due to deeper penetration of the organ by radiation. Inadequate cooling between pulses also predisposes to injury by cosmetic lasers. KEYWORDS: Lasers, injury, cosmetic, safety, periorbital, eyelid, laser hair removal, resurfacing Ocular Injury in Cosmetic Laser Treatments of the Face by AMY HUANG, MD; ARIANNA PHILLIPS, BS; TONY ADAR, MD; and ANDREA HUI, MD Drs. Huang, Adar, and Hui are with the Department of Dermatology at the State University of New York Downstate Medical Center in Brooklyn, New York. Ms. Phillips and Dr. Hui are with Bay Area Cosmetic Dermatology in San Francisco, California. J Clin Aesthet Dermatol. 2018;11(2):15–18 FUNDING: No funding was provided for this article. DISCLOSURES: The authors have no conflicts of interest to relevant to the content of this article. CORRESPONDENCE: Andrea M. Hui, MD; Email: hui.andrea@gmail.com